Deep Roots

Let’s face it—we are nearing the end of our annual drought season, when it typically doesn’t rain for five to six months. In order to survive, our plants require the best growing conditions that we can provide. Our irrigation systems need to be spot-on to provide maximum coverage and apply just enough water to replace the moisture lost through evapotranspiration so we don’t over- or under-irrigate.

What about those plants that are on the outer perimeter, not being irrigated? And how about the native plants forming their own hydrozone? These plants need to be tough to withstand adverse conditions if proper irrigation is not available.

California poppy root

This lesson came to light this week as I pulled out a California poppy (Eschscholzia californica) that was at the end of its growing season. It was growing on the edge of the circular drive that Jack was enlarging. To my amazement, this native flower had roots that far exceeded my expectation of an annual.

Typically annuals are considered high-water-users because they have shallow roots. We place them in areas with other high-water-using plants. However, I started to rethink this generalization after seeing the root system on this poppy.

Exploring the web confirmed what I knew—most California native annuals can withstand extreme temperatures and harsh environments. What I didn’t realize is that some of their root systems can grow over twenty feet deep and draw on moisture and nutrients deep within the earth.

Deep roots can aerate the hardpan soil, allowing for better drainage. As the plants die off, the dead roots build up the soil and improve the water-holding capacity as composting occurs through root decay. The organic matter left is like manna from heaven!

A good example of this was shared by a gentleman maintaining the city grounds in San Jose. He explained that the city had a terrible time with an area flooding, which they were trying to correct. I was admiring the beautiful rose garden surrounding us as the story unfolded. The roses were glorious—insect and disease-free. It was then that I learned this was the site of the recurring flood. The storyteller explained that they experimented by planting sunflower seeds in the flood area one spring. The deep roots eliminated the flooding problem by breaking through the hardpan that created the winter lake. The problem disappeared, and they dedicated the new-found area to the rose garden.

Do you have an area of your garden that doesn’t drain well? Deep-rooted native annual and perennial plants may correct a soggy condition. This is a wonderful time to take a hike to see what plants thrive in our Marin hills and valleys. It is also the time of year to collect native wildflower seeds for sowing next spring’s color.

Join us at EcoFair Marin this Sunday, September 9, at Marin County Fairgrounds

EcoFair Marin is the second annual community celebration to inspire a healthy and sustainable Marin. Enjoy speakers, exhibitors, “how to” demonstrations, music and activities for the whole family. Be sure to drop by MMWD’s booth (#8 in the iLive section) to say hello! General admission is $5; children under 17 are free.

Scott,
Healthy plants resist insects and pests. It is plants that are distressed that seem subject to their attack. The object is to create that healthy environment. Now if I can only figure out how to make that happen to deter rabbits!
Charlene